Caliper of a disc brake

ABSTRACT

A caliper of a disc brake comprises a caliper body having a first half-body and a second half-body. The first half-body has a first hole and the second half-body has a second hole, coaxial with the first hole.  
     The holes receive at least one connecting member suitable for firmly securing the first half-body to the second half-body and further provide an attachment seat capable of receiving an attachment member suitable for firmly securing said caliper body to the fork of a motorcycle.

FIELD OF THE INVENTION

[0001] The present invention relates to a caliper of a disc brake,particularly, but not solely, intended for use in the motorcycle sector.

BACKGROUND OF THE INVENTION

[0002] In the field of fixed type disc brake calipers, intended inparticular for use in the motorcycle sector, the known embodimentsprovide a caliper body as two half-bodies separate from each other andconnected by connecting screws which firmly secure the first half-bodyto the second half-body.

[0003] Furthermore, said caliper body is provided with attachment meanswhich permit the connection of the caliper body to the support, and aredisposed at lugs protruding from the caliper body itself.

[0004] However, the calipers produced according to the prior art areoften too bulky and often unaesthetic, since they project too much fromthe support, especially in the case of calipers intended for motorcycleuse.

[0005] A need was therefore felt to produce a caliper body that can beassociated with a support, for example the fork of a motorcycle, andwhich is reduced in overall dimensions and reliable in use.

[0006] The problem underlying the present invention is that of devisinga disc brake caliper which has structural and functional characteristicssuch as to fulfil the aforesaid requirements and at the same time toremedy the drawbacks mentioned with reference to the prior art.

SUMMARY OF THE INVENTION

[0007] This problem is solved by a caliper according to claim 1. Theclaims dependent thereupon describe alternative embodiments.

[0008] In the continuation of the description, reference will be made tothe terms “circumferential”, “radial” and “tangential”, to be understoodwith reference to the directions of a disc that can be associated withthe caliper according to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The characteristics and advantages of the caliper according tothe present invention will become clear from the following descriptionof a preferred non-limiting exemplary embodiment, in which

[0010]FIG. 1 shows a side view of a caliper body according to theinvention;

[0011]FIG. 2 shows a radial view of the caliper body of FIG. 1;

[0012]FIG. 3 shows a partial section of the caliper body of FIG. 2,obtained along the section line A-A;

[0013]FIG. 4 shows a rear elevation of the caliper body of FIG. 1,obtained in the viewing direction R in FIG. 1;

[0014]FIG. 5 shows a front elevation of the caliper body of FIG. 1,obtained in the viewing direction R in FIG. 1;

[0015]FIG. 6 shows a partial section of the caliper body of FIG. 1,obtained along the line B-B of FIG. 1;

[0016]FIG. 7 shows a partial section of the caliper body of FIG. 1,obtained along the line C-C, according to a first alternative embodimentof the system of connection and attachment to the support, and

[0017]FIG. 8 shows a partial section of the caliper body of FIG. 1,obtained along the line C-C, according to a further alternativeembodiment of the system of connection and attachment.

DETAILED DESCRIPTION OF THE INVENTION

[0018] With reference to the appended drawings, the reference 1indicates generally a caliper comprising a caliper body 2.

[0019] Said caliper body 2 comprises a first half-body 2 a and a secondhalf-body 2 b, separable from the first.

[0020] In other words, said first half-body 2 a and said secondhalf-body 2 b are produced separately, for example by machining astarting semifinished part, obtained by casting, for example by means ofmachining carried out with machine tools.

[0021] Each half-body 2 a, 2 b comprises a central region which, withreference to the directions of the disc brake that can be associatedwith the caliper body 2, extends substantially tangentially.

[0022] In an assembly configuration of the disc brake, in which thecaliper body 2 is arranged straddling the brake disc, said centralregions of the caliper body 2 are disposed radially to the disc at thebraking band of the brake disc.

[0023] The caliper body 2 comprises connection means suitable for firmlysecuring the first half-body 2 a to the second half-body 2 b.

[0024] Said connection means, in a preferred embodiment, providehole/screw systems which make it possible to connect the first half-body2 a to the second half-body 2 b.

[0025] In particular, the first half-body 2 a has a first hole 6 a andthe second half-body 2 b has a second hole 6 b disposed, in a conditionwhere the first half-body 2 a is associated with the second half-body 2b, so as to be coaxial with the first hole 6 a.

[0026] The first hole 6 a and the second hole 6 b are capable ofreceiving at least one connecting member suitable for firmly securingthe first half-body 2 a to the second half-body 2 b.

[0027] In a preferred embodiment, said connecting member is a screw.

[0028] Moreover, in a preferred embodiment, said connection meanscomprise a plurality of hole/screw systems 9, 10 suitable for firmlysecuring the first half-body 2 a to the second half-body 2 b.

[0029] Said hole/screw systems are preferably disposed in a peripheralregion adjacent and radially external to said central region, in acircumferential direction with respect to the brake disc that can beassociated with the caliper body 2.

[0030] Moreover, the caliper body 2 has attachment means suitable forfirmly securing said caliper body 2 to a fixed support 12, for example afork of a motorcycle.

[0031] In particular, said attachment means comprise said first hole 6 aof the first half-body 2 a and said second hole 6 b of the secondhalf-body 2 b. Said first and second hole are capable of receiving atleast one attachment member suitable for firmly securing the secondhalf-body 2 b to the support 12.

[0032] In other words, said first hole 6 a and said second hole 6 bprovide a single seat in common between said connection means and saidattachment means.

[0033] In an alternative embodiment, a single connection and attachmentmember 8 firmly secures said first half-body 2 a to said secondhalf-body 2 b and, at the same time, said second half-body 2 b to saidsupport 12 (FIG. 7).

[0034] In other words, in said alternative embodiment, the attachmentmember for attachment to the support 12 also constitutes the connectingmember for firmly securing the half-bodies.

[0035] In a further alternative embodiment, said single seat isengageable with a first connecting member 8 a which firmly secures thefirst half-body 2 a and the second half-body 2 b, and with a separateattachment member 8 b which firmly secures the second half-body 2 b tothe fixed support 12 (FIG. 8).

[0036] In yet other words, said seat is engageable only partially by thefirst connecting member 8 a, leaving a portion of the seat free andengageable by the attachment member 8 b which firmly secures the secondhalf-body 2 b to the support 12.

[0037] In an alternative embodiment, said first hole 6 a of the firsthalf-body 2 a has a diameter different from the diameter of the secondhole 6 b of the second half-body 2 b. Preferably, said first hole 6 a ofthe first half-body 2 a has a diameter smaller than the diameter of thesecond hole 6 b of the second half-body 2 b.

[0038] In a further alternative embodiment, said second hole 6 b of thesecond half-body 2 b has a first portion 9 a and a second portion 9 b,said portions having a different diameter. In particular, said firstportion 9 a is close to the first hole 6 a of the first half-body 2 aand has a diameter smaller than the diameter of the second portion 9 b.

[0039] Advantageously, said portions of different diameter make itpossible to use connecting members between the first and the secondhalf-body having a diameter smaller than the diameter of the attachmentmembers for attaching the caliper body to the support 12.

[0040] Preferably, said attachment means further comprise a third hole20, produced in a lug 22 protruding from the central region of thesecond half-body 2 b, said lug preferably extending in a substantiallyradial direction.

[0041] In a preferred embodiment, the hole/screw systems 9, 10 of theconnection means between the first half-body 2 a and the secondhalf-body 2 b are disposed circumferentially with respect to the brakedisc that can be associated with the caliper body, or are intersected bythe same circumference concentric with the axis of the brake disc thatcan be associated with said caliper body (2).

[0042] In a further embodiment, the hole/screw systems 9, 10 of theconnection means between the first half-body 2 a and the secondhalf-body 2 b are disposed circumferentially with respect to the brakedisc that can be associated with the caliper body, on a circumferenceexternal to the circumference on which lies the axis of said third hole20 of the attachment means.

[0043] Each central region of the caliper body 2 provides a housing 23for at least one respective pad 24.

[0044] In a preferred embodiment, each pad 24 consists of a plate 26 onwhich friction material 28 is supported.

[0045] The plate 26 is provided with a protuberance 29 in which there isprovided an eye 30 suitable for engaging with a pin 32, preferably withclearance.

[0046] The plate 26 also provides a support area 34 which bears on asupport member 36 of the caliper body 2.

[0047] Moreover, said plate 26 provides a reaction area 38, whichengages with a reaction rib 40 of the caliper body 2.

[0048] Said eye/pin system and said support area/support member systemprovide bearing and suspension means for the caliper body 2 which aresuitable for maintaining the pad in position and opposing the action ofthe braking forces during braking.

[0049] Moreover, the caliper 1 is provided with thrust means suitablefor acting on the pads received in the respective half-bodies 2 a, 2 bfor butting them against the braking band of the brake disc andproducing braking.

[0050] Said thrust means comprise at least one piston slidinglyreceived, sealed, in a respective seat, said seat being fluidlyconnected to a hydraulic circuit containing brake fluid, said hydrauliccircuit being at least partially received in said caliper body 2.

[0051] In particular, said hydraulic circuit comprises a fluid inlet 30at which means are provided for the hydraulic connection between a tubecoming from a pump, that can be actuated for example, manually, by meansof a lever, and said caliper body.

[0052] Preferably, said fluid inlet 30 is provided at the secondhalf-body 2 b.

[0053] Said hydraulic circuit provides a first section 32 a, provided insaid first half-body 2 a and fluidly connected to at least one seat fora piston of the first half-body 2 a.

[0054] Said fluid inlet 30 is further fluidly connected to a secondsection 32 b of the hydraulic circuit, provided in said second half-body2 b of the caliper body 2, and connected to at least one seat for apiston of the second half-body 2 b.

[0055] Said first section 32 a and said second section 32 b of thehydraulic circuit are fluidly connected through a connecting aperture33.

[0056] The connection between said first half-body 2 a and said secondhalf-body 2 b is suitable for producing the hydraulic connection betweensaid first section 32 a and said second section 32 b of the hydrauliccircuit.

[0057] In particular, in the embodiment which provides the firstconnecting member 8 a suitable for firmly securing the first half-body 2a and the second half-body 2 b, and the separate attachment member 8 bwhich firmly secures the second half-body 2 b to the support 12, saidfirst connecting member 8 a is suitable for producing a sealed hydraulicconnection between the first section 32 a and the second section 32 b ofthe hydraulic circuit.

[0058] In other words, in said embodiment, though the seat is notengaged with the attachment member 8 b, or the mounting on the support12 not carried out, said first half-body 2 a and said second half-body 2b are nevertheless firmly secured to each other, in order to ensure theseal between said sections of the hydraulic circuit.

[0059] Moreover, in an alternative embodiment, said hydraulic circuitcomprises a bleeder seat 34 capable of receiving a bleeder plug. Saidbleeder seat 34 is fluidly connected to said fluid inlet 30 by a bleedersection 35.

[0060] In an assembly configuration of the disc brake, each pad isreceived in the respective housing of the caliper body 2, suspended bymeans of the eye 30 on the pin 32 and bearing on the support member 36with the support area 34.

[0061] The first half-body 2 a is connected to the second half-body 2 bby way of said connection means, in particular by way of the hole/screwsystems 9, 10.

[0062] The connecting member 8 a is engaged in the seat provided by thefirst hole 6 a and the second hole 6 b and ensures a sealed connectionbetween the first section 32 a and the second section 32 b of thehydraulic circuit.

[0063] The attachment member 8 b firmly secures the second half-body 2 bto the fixed support 12, for example to the front fork of a motorcycle,in order to transmit the braking action, during braking, from the padsto said fixed support 12 (FIG. 8).

[0064] In one embodiment, the single connection and attachment member 8engages the seat produced by the first hole 6 a and the second hole 6 b,connecting the first half-body 2 a to the second half-body 2 b and, atthe same time, the caliper body 2 to the support 12 (FIG. 7).

[0065] In addition, a further screw, engaged with the third hole 20,completes the attachment of the caliper body 2 to the fixed support 12.

[0066] The fluid inlet 30 is connected to the tube coming from the pump.

[0067] In normal operation of the disc brake, the action of the driverof the vehicle, for example a motorcycle, pressurizes the brake fluid,for example by actuation of the lever of the pump.

[0068] The brake fluid under pressure acts on the pistons which, slidingin the respective seats, act on the pads, causing them to butt againstthe braking band of the brake disc, producing braking.

[0069] The braking action is transmitted from the pad to the reactionrib, against which the reaction portion of the pad abuts, and from saidrib to the caliper body, discharging to the support 12.

[0070] Said attachment means ensure the connection between the caliperbody and said fixed support 12.

[0071] Unusually, the caliper according to the invention is compact andreduced in dimensions, and particularly, but not solely, suitable foruse in the motorcycle field.

[0072] Advantageously, in addition, the connection means and theattachment means are at least partially integrated, sharing a seatprovided by a plurality of holes, limiting the overall dimensions of thecaliper body.

[0073] According to a further advantageous feature, the caliperaccording to the invention provides at least one connecting member whichsimultaneously connects the half-bodies of the caliper body and attachesthe caliper body to the fixed support.

[0074] Advantageously, in addition, the seat provided by the union ofthe holes of a half-body, shared by the connection means and by theattachment means, is partially engageable by a first connecting memberwhich firmly secures the half-bodies, and by a separate attachmentmember which firmly-secures the caliper body to the support.

[0075] According to this advantageous feature, the half-bodies of thecaliper body are connected at the time of production by specializedtechnicians, who tighten the connecting screws to design values capableof ensuring correct behaviour of the caliper body with respect tostresses.

[0076] Moreover, advantageously, the separate connecting member makes itpossible to hold the half-bodies of the caliper body together even whenmounting on the fixed support has not been carried out.

[0077] Moreover, the separate connecting member makes it possible tocarry out the screwing operation in the workshop, according to screwingmodes and conditions which ensure the hydraulic seal between thesections of the hydraulic circuit disposed in the respectivehalf-bodies.

[0078] It is clear that an expert in the field may apply numerousvariations to the caliper provided with the connection and attachmentsystem described above, all however to be understood as included withinthe scope of teaching as defined by the following claims.

1. A caliper of a disc brake that can be associated with a fixed supportfor the transfer of the braking action from a disc to said fixedsupport, said caliper comprising: a caliper body having a firsthalf-body and a second half-body, separable from the first, wherein saidfirst half-body has a first hole and said second half-body has a secondhole, which in conditions where the first half-body is associated withthe second half-body is coaxial with the first hole, said holes beingcapable of receiving at least one connecting member suitable for firmlysecuring said first half-body to said second half-body: and wherein saidfirst hole and said second hole further provide an attachment seatcapable of receiving an attachment member suitable for firmly securingsaid caliper body to said support.
 2. A caliper according to claim 1,wherein said attachment member for attaching the caliper body to thesupport is a member separate from said connecting member for connectingthe half-bodies of the caliper body.
 3. A caliper according to claim 1,wherein said seat provided by said first and second hole, and engaged bysaid connecting member has a free portion not engaged by said connectingmember.
 4. A caliper according to claim 3, wherein said free portion ofthe seat provided by said first hole and said second hole is capable ofreceiving the attachment member for attachment between the caliper bodyand the support.
 5. A caliper according to claim 2, wherein said secondhole has a first portion and a second portion, said first portion havinga diameter smaller than the diameter of said second portion.
 6. Acaliper according to claim 5, wherein said connecting member has anominal diameter smaller than the nominal diameter of the attachmentmember.
 7. A caliper according to claim 1, wherein said connection meansare suitable for ensuring the fluid connection between a first sectionand a second section of a hydraulic circuit of said caliper body, saidfirst section being provided in the first half-body and said secondsection being provided in said second half-body.
 8. A caliper accordingto claim 7, wherein said fluid connection is ensured independently ofthe mounting of the caliper body on the support.
 9. A caliper accordingto claim 1, wherein said attachment member for attaching the caliperbody to the support also constitutes the connecting member forconnection between the first half-body and the second half-body.
 10. Acaliper according to claim 9, wherein said attachment and connectionmember comprises a screw suitable for simultaneously engaging the firsthalf-body, the second half-body and the fixed support.
 11. A caliperaccording to claim 1, wherein said connection means provide a pluralityof hole/screw systems for firmly securing said first half-body to saidsecond half-body.
 12. A caliper according to claim 11, wherein saidhole/screw systems are intersected by the same circumference concentricwith the axis of the brake disc that can be associated with said caliperbody.
 13. A caliper according to claim 1, wherein said attachment meanscomprise a third hole provided in a lug protruding from a central regionof the second half-body.
 14. A caliper according to claim 13, whereinhole/screw systems of the connection means are disposed on acircumference external with respect to the circumference on which liesthe axis of said third hole of the attachment means.
 15. A caliperaccording to claim 2, wherein said seat provided by said first andsecond hole, and engaged by said connecting member has a free portionnot engaged by said connecting member.
 16. A caliper according to claim15, wherein said free portion of the seat provided by said first holeand said second hole is capable of receiving the attachment member forattachment between the caliper body and the support.
 17. A caliperaccording to claim 2, wherein said connection means are suitable forensuring the fluid connection between a first section and a secondsection of a hydraulic circuit of said caliper body, said first sectionbeing provided in the first half-body and said second section beingprovided in said second half-body.
 18. A caliper according to claim 17,wherein said fluid connection is ensured independently of the mountingof the caliper body on the support.
 19. A caliper according to claim 2,wherein said connection means provide a plurality of hole/screw systemsfor firmly securing said first half-body to said second half-body.
 20. Acaliper according to claim 19, wherein said hole/screw systems areintersected by the same circumference concentric with the axis of thebrake disc that can be associated with said caliper body.
 21. A caliperaccording to claim 2, wherein said attachment means comprise a thirdhole provided in a lug protruding from a central region of the secondhalf-body.
 22. A caliper according to claim 21, wherein hole/screwsystems of the connection means are disposed on a circumference externalwith respect to the circumference on which lies the axis of said thirdhole of the attachment means.
 23. A disc brake comprising at least onecaliper according to claim 1.